To paraphrase what Kevin Leavitt recently posted, wrist locks are merely one tool in a toolbox of techniques. In order to use them successfully, you must have a fundamental skill set at your command. These include having situational awareness, getting off the line of attack, blending with the attack, taking the attacker's balance and then applying the lock with the appropriate amount of force. Those skills require both an instructor and practice to develop. Without the foundation, simply grasping or catching an attacker's wrist and trying to apply a lock is almost fruitless. It can be done, but the success rate is very, very low.

Your basic concept of trying to find a less-violent response to an attack is worthwhile. Kids, particularly inner city kids, are faced with real-world threats today and they do need help to protect themselves. You might consider visiting various martial arts dojo in your area and discussing your concerns and ideas with the instructors. They may put you on a successful track.

Something that continues to bother me from your first post was the idea that a kid could use the "Aikido wrist lock dancing" to avoid being disciplined at school. While some schools have a zero tolerance policy and discipline aggressor and victim alike, many investigate these events and discipline only the aggressor. It struck me that the victim in your scenario would have some sort of plausible deniability and that isn't much of a lesson for our kids either.

Lastly, I'm still not sure whether you are an educator yourself or a student. It matters in this discussion.